It is conventionally known that some derivatives having a nucleic acid bound to then four-membered rings have antiviral action. Examples of such derivatives include cyclobutyl purine derivatives (see Patent Documents 1 to 3, for example) and oxetanocin derivatives having a nucleic acid bound to their oxetane rings (see Patent Document 4, for example).
On the other hand, as substances that promote angiogenesis, neurocyte growth, and the like, living organism-derived growth factors such as fibroblast growth factors (FGFs), platelet-derived growth factors (PD-ECGFs), vascular endothelial growth factors (VEGFs), and nerve growth factors (NGFs) are known. Some of these growth factors are used as active ingredients in wound healing agents, hair growth agents, and the like.